Fluid-filled underground transmission cable condition assessment

Many underground power cable users are faced with aging fluid-filled transmission cables that have exceeded their design life of 30-40 years. Major and possibly costly decisions have to be made whether to replace or to continue to use the existing cable system. This paper presents a condition assessment strategy focused on fluid-filled cables that involves a combination of visual observations through on-site inspections, laboratory diagnostics, on-site diagnostics, operation reports and data trending.